1. Field of the Invention
The present invention relates to an energy store and a charging method.
2. Description of Related Art
An electric battery includes a number of electric energy cells which are connected to one another in series. To charge the battery, a predetermined charging current is led through the energy cells. During the course of the charging process, the cell voltages of the energy cells in each case approach a predetermined maximum cell voltage. Some batteries may react sensitively to a charging error, such as overcharging. Lithium ion batteries may burst, for example, which may be accompanied by an explosion or a fire.
In order to avoid a charging error and to end the charging process in time, it is customary to switch off the charging current when one of the energy cells has reached the maximum cell voltage assigned to it. In this context, however, the state of charge of other cells, whose cell voltages are below the respectively specified maximum cell voltages, may not yet have reached a maximum state of charge, so that on an overall basis, the battery is only partially charged.